var a:number = 0


function add(x: number, y: number): number {
  return x + y;
}
// add('1','2')
interface SquareConfig {
  color?: string;
  width?: number;
}

class GenericNumber<T> {
  constructor(private a:T){}
}

function identity<T>(arg: T): T {
  return arg;
}
let output = identity<string>("myString");